Trait evolution rates shape continental patterns of species richness in North America's most diverse angiosperm genus (Carex, Cyperaceae)  

作　　者：Jocelyn E.Pender Andrew L.Hipp Marlene Hahn Julian R.Starr 

机构地区：[1]Department of Biology,University of Ottawa,30 Marie Curie,Ottawa,ON K1N 6N5,Canada [2]Ottawa Research and Development Centre,Agriculture and Agri-Food Canada,960 Carling Ave.,Ottawa,ON K1A 0C6,Canada [3]The Morton Arboretum,4100 Illinois Route 53,Lisle,IL 60532-1293,USA

出　　处：《Journal of Systematics and Evolution》2021年第4期763-775,共13页植物分类学报（英文版）

基　　金：support was provided by National Science and Engineering Research Council of Canada(NSERC)Discovery Grants to JRS(Nos.RGPIN-342278-2013 and RGPIN-2018-04115);a NSERC Graduate Scholarships-Master's Scholarship(No.558809)to JEP;a US National Science Foundation Award(No.1255901)to ALH.

摘　　要：Ecological opportunity has been associated with increases in diversification rates across the tree of life.Under an ecological diversification model,the emergence of novel environments is hypothesized to promote morpho-and ecospace evolution.Whether this model holds at the clade level within the most species-rich angiosperm genus found in North America(Carex,Cyperaceae)is yet to be tested.Recent works demonstrate a temporal coupling of climate cooling and widespread colonization of Carex in North America,implicating ecological diversification.In addition,research has consistently found asymmetric patterns of lineage-level diversification in the genus.Why does variation in clade sizes exist in the genus?Is ecological diversification involved?In this study,we tested whether rates of morphological and ecological trait evolution are correlated with clade-level species richness in Carex of North America north of Mexico.We constructed a phylogeny of 477 species-an almost complete regional sample.We estimated rates of evolution of morphological traits,habitat,and climatic niche and assessed whether differences in rates of evolution correlate with species richness differences in replicate non-nested sister clades.Our work demonstrates significant positive correlations between climatic niche rates,habitat and reproductive morphological evolution,and species richness.This coupling of trait and niche evolution and species richness in a diverse,continental clade sample strongly suggests that the ability of clades to explore niche and functional space has shaped disparities in richness and functional diversity across the North American flora region.Our findings highlight the importance of the evolutionary history of trait and niche evolution in shaping continental and regional floras.

关 键 词：CAREX climatic niche continental diversity ecological diversification ecological opportunity lineage diversification morphology SEDGES species richness trait evolution 

分 类 号：Q94[生物学—植物学]